Many of the children, whose average age was 5, were hospitalized
with severe illness.

Parents should be cautious about pet frogs, which are often kept
in home aquariums, and amphibians and reptiles in general, warned
Shauna Mettee Zarecki, lead author of a new report and a public
health advisor with the U.S. Centers for Disease Control and
Prevention.

"Families just weren't aware that there was a risk from these frogs or reptiles or amphibians in general," Mettee Zarecki said. "Any amphibians, particularly these frogs, should not be in homes where there are children less than 5 years old."

Medical researchers found 376 cases of infection with a type of
salmonella in 44 states from 2008 to 2011. More than two-thirds
were children under the age of 10.

Salmonella is spread by a bacteria and causes diarrhea,
abdominal cramps and fever that can last for several days, Mettee
Zarecki said. Most people recover after about a week, but some need
to be hospitalized, and the disease can be deadly.

About 30 percent of the infected people in this outbreak were
hospitalized. Fortunately, none died.

Diagnosing the strain of salmonella requires testing a stool
sample, and many physicians and patients don't bother to take that
step, Mettee Zarecki said. For that reason, the CDC doesn't know
how widespread the outbreak actually was. But previous research
suggests that there may be 16 cases for each reported case, making
it possible that this outbreak affected some 6,000 people.

The researchers linked the outbreak to a frog breeding facility
in Madera County, Calif. The CDC didn't identify the facility, and
Mettee Zarecki said it's not clear how the salmonella infection
spread to the frogs, which transmitted it through their feces.

Children are especially vulnerable to salmonella, Mettee Zarecki
said, and it appears that they were infected through contact with
contaminated water from frog habitats, such as aquariums.

Dr. Robert Frenck, professor of pediatrics with the division of
infectious diseases at Cincinnati Children's Hospital Medical
Center, noted that it's possible to be infected with salmonella by
drinking contaminated water. But it seems to be more commonly
transmitted either from food contaminated with the bacteria or
direct contamination of the hand that subsequently goes in the
mouth, said Frenck, who was not involved with the study.

In one case, a family cleaned an aquarium in the same kitchen
sink that they used to bathe their child and kept baby bottles
nearby. The child became infected and was hospitalized.

Owners of the frogs should empty and wash aquariums outside the
home to avoid infecting sinks and bathtubs. And because any
amphibians or reptiles could carry salmonella, they shouldn't be
around kids under 5 at all, Mettee Zarecki said, nor around anyone
who has a weakened immune system.

"There have been a number of outbreaks associated with a variety of pets, and amphibians have been known to carry salmonella. We always try to tell people that reptiles like turtles and snakes are a significant source of potential infection," she said. "But this is the first time they have been linked to an illness on this scale."

Dr. Pascal James Imperato, dean of the School of Public Health
at SUNY Downstate Medical Center in Brooklyn, N.Y., recommends that
children should not have certain kinds of pets, including chicks
and ducklings.

"If [people] do buy them, they need to ensure that everyone in the household -- children and adults -- who have contact with them, should thoroughly wash their hands with soap and water after touching or handling them and the objects with which these pets come into contact, such as litter for chicks and ducklings, and terrarium materials for frogs and turtles," Imperato said.

Also make sure that children don't kiss the pets, he said.

The report was released online March 11 in advance of
publication in the April print issue of
Pediatrics.

More information

For more about
salmonella, visit the U.S. National Library of Medicine.

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.